21,894
社区成员




$s =<<< TXT
abcxyz
qwerty
[abc]aaaaaaaa
bbbbbbbbb
ccccccccc[/abc]
poiuyt
lkjhgf
[abc]
dddddd
eeeeeee
ffff[/abc]
poiuy
asdfg
TXT;
echo preg_replace('#\[abc].+?\[/abc]#se', 'preg_replace("/[\r\n]+/","","$0")', $s);
abcxyz